This document provides an introduction to composite materials, including definitions, types, advantages, applications, costs, manufacturing processes, and material properties. It defines composites as materials made of two or more inherently different materials combined to produce properties superior to the individual components. Composites are classified by matrix (polymer, metal, ceramic) and reinforcement (fiber, particle, flake). Common fiber reinforcements include glass, carbon, and aramid fibers. Manufacturing processes include hand lay-up, filament winding, molding, and continuous lamination.
The document discusses different types of composite materials including their definitions, advantages, classifications, and properties. It describes metal matrix composites, ceramic matrix composites, and polymer matrix composites. Key points include that composites can have high strength and stiffness yet be lightweight, and that their properties depend on the constituent materials, geometry, and interactions between phases.
The document discusses different thermal spraying coating processes. It describes combustion flame spraying, high velocity oxy-fuel spraying, two wire electric arc spraying, plasma spraying, and vacuum plasma spraying. Plasma spraying allows any material to be coated and produces coatings with very low porosity. Carbon nanotubes were added to TiO2 coatings via plasma spraying to improve tribological properties. Test results showed the TiO2-CNT coatings had lower friction and 96% less wear than pure TiO2 coatings due to reinforcement and lubricating effects of the carbon nanotubes.
The matrix in a composite is the continuous phase that transfers stress to the dispersed phase. Common matrix materials include metals, ceramics, and polymers. There are two possible strengthening mechanisms for particle reinforced composites: load transfer from the matrix to the particles and restriction of dislocation movement. The Young's modulus of a large particle composite can be calculated using upper and lower bounds. The critical length (Lc) of a fiber depends on factors like fiber diameter and matrix-fiber bond strength. Fibers of different lengths experience different stress distributions relative to the critical fiber length.
This document discusses metal matrix composites (MMCs), which are composite materials with at least two constituent parts including a metal. MMCs can be classified based on their composition and reinforcement materials. Common reinforcement materials include silicon carbide, titanium carbide, and carbon nanotubes. Production methods for MMCs include stir casting and powder metallurgy. MMCs exhibit improved properties over unreinforced metals like high strength and stiffness. Applications of MMCs span aerospace, automotive, and other industries. The document outlines advantages like heat resistance and disadvantages like higher cost compared to unreinforced metals.
This document summarizes super alloys, including their properties, applications, classifications, microstructure, and heat treatment. Super alloys exhibit high strength and corrosion/oxidation resistance at high temperatures due to strengthening from solid solution strengthening and precipitation hardening. They are classified based on their primary metal (nickel, iron, cobalt) and are used in applications such as jet engines and gas turbines due to their high temperature capabilities. Their microstructure includes a gamma matrix and gamma prime precipitates that increase strength. Heat treatments are used to control the precipitates and carbides for optimal properties.
Vacuum bag molding is an open mold technique used for thermoset composites involving hand layup and vacuum bagging. Vacuum bagging uses a vacuum bag to apply even pressure over composite materials to consolidate them. It involves placing release fabrics, breather materials, and vacuum bags over molds with resin-coated components. Applying vacuum pressure draws air out and uses atmospheric pressure to hold components in place until the resin cures.
Carbon-carbon composites are lightweight materials made of carbon fibers reinforced with a carbon matrix. They were first developed in 1958 but not extensively researched until the Space Shuttle Program. Carbon-carbon composites can withstand temperatures over 3000°C and are strong, rigid, and lightweight. They are produced by infiltrating carbon fibers with liquid or gas precursors and pyrolyzing them to leave behind a carbon matrix.
This document discusses metal matrix composites (MMC) and ceramic matrix composites (CMC). It defines composites as materials created by combining two or more materials, with fibers providing strength and stiffness. MMCs use a metal matrix reinforced with fibers or particles, while CMCs use a ceramic matrix. The matrix holds the reinforcements and transfers load. Common reinforcement types are particulate, continuous fiber, and discontinuous fiber. Applications of MMCs and CMCs include automotive parts, armor, aircraft components, and industrial systems due to their high strength, stiffness, temperature resistance. Manufacturing methods include powder blending, vapor deposition, and liquid infiltration.
The document discusses different types of composite materials including their definitions, advantages, classifications, and properties. It describes metal matrix composites, ceramic matrix composites, and polymer matrix composites. Key points include that composites can have high strength and stiffness yet be lightweight, and that their properties depend on the constituent materials, geometry, and interactions between phases.
The document discusses different thermal spraying coating processes. It describes combustion flame spraying, high velocity oxy-fuel spraying, two wire electric arc spraying, plasma spraying, and vacuum plasma spraying. Plasma spraying allows any material to be coated and produces coatings with very low porosity. Carbon nanotubes were added to TiO2 coatings via plasma spraying to improve tribological properties. Test results showed the TiO2-CNT coatings had lower friction and 96% less wear than pure TiO2 coatings due to reinforcement and lubricating effects of the carbon nanotubes.
The matrix in a composite is the continuous phase that transfers stress to the dispersed phase. Common matrix materials include metals, ceramics, and polymers. There are two possible strengthening mechanisms for particle reinforced composites: load transfer from the matrix to the particles and restriction of dislocation movement. The Young's modulus of a large particle composite can be calculated using upper and lower bounds. The critical length (Lc) of a fiber depends on factors like fiber diameter and matrix-fiber bond strength. Fibers of different lengths experience different stress distributions relative to the critical fiber length.
This document discusses metal matrix composites (MMCs), which are composite materials with at least two constituent parts including a metal. MMCs can be classified based on their composition and reinforcement materials. Common reinforcement materials include silicon carbide, titanium carbide, and carbon nanotubes. Production methods for MMCs include stir casting and powder metallurgy. MMCs exhibit improved properties over unreinforced metals like high strength and stiffness. Applications of MMCs span aerospace, automotive, and other industries. The document outlines advantages like heat resistance and disadvantages like higher cost compared to unreinforced metals.
This document summarizes super alloys, including their properties, applications, classifications, microstructure, and heat treatment. Super alloys exhibit high strength and corrosion/oxidation resistance at high temperatures due to strengthening from solid solution strengthening and precipitation hardening. They are classified based on their primary metal (nickel, iron, cobalt) and are used in applications such as jet engines and gas turbines due to their high temperature capabilities. Their microstructure includes a gamma matrix and gamma prime precipitates that increase strength. Heat treatments are used to control the precipitates and carbides for optimal properties.
Vacuum bag molding is an open mold technique used for thermoset composites involving hand layup and vacuum bagging. Vacuum bagging uses a vacuum bag to apply even pressure over composite materials to consolidate them. It involves placing release fabrics, breather materials, and vacuum bags over molds with resin-coated components. Applying vacuum pressure draws air out and uses atmospheric pressure to hold components in place until the resin cures.
Carbon-carbon composites are lightweight materials made of carbon fibers reinforced with a carbon matrix. They were first developed in 1958 but not extensively researched until the Space Shuttle Program. Carbon-carbon composites can withstand temperatures over 3000°C and are strong, rigid, and lightweight. They are produced by infiltrating carbon fibers with liquid or gas precursors and pyrolyzing them to leave behind a carbon matrix.
This document discusses metal matrix composites (MMC) and ceramic matrix composites (CMC). It defines composites as materials created by combining two or more materials, with fibers providing strength and stiffness. MMCs use a metal matrix reinforced with fibers or particles, while CMCs use a ceramic matrix. The matrix holds the reinforcements and transfers load. Common reinforcement types are particulate, continuous fiber, and discontinuous fiber. Applications of MMCs and CMCs include automotive parts, armor, aircraft components, and industrial systems due to their high strength, stiffness, temperature resistance. Manufacturing methods include powder blending, vapor deposition, and liquid infiltration.
This document presents an overview of metal matrix composites (MMCs). It defines MMCs as composites with at least two constituent parts, one being a metal matrix and the other being another material like another metal, ceramic, or organic compound. The document discusses the composition, production, properties and applications of MMCs. It notes that MMCs combine properties like high strength and stiffness with lower density compared to unreinforced metals. Common reinforcement materials in MMCs include fibers of boron, silicon carbide, and alumina. The document outlines some important MMC systems and their advantages like higher temperature capability and strengths, as well as disadvantages like higher cost. Applications discussed include automotive and aerospace parts.
This document provides an overview of composite materials. It defines composites as materials made of two or more constituent materials with distinct properties. Composites consist of a reinforcement material embedded in a matrix to hold the reinforcements together. Common reinforcements include fibers, particles or flakes. The matrix materials are typically polymers, metals or ceramics. The document discusses various types of composites and their applications in areas like transportation, aerospace, sports equipment and infrastructure. Composites offer advantages like high strength, stiffness and corrosion resistance combined with lighter weight.
Ceramic matrix composites (CMCs) consist of ceramic fibers embedded in a ceramic matrix to form a ceramic fiber reinforced ceramic material. They improve the strength and toughness of brittle ceramics. CMCs can be reinforced with either short or continuous fibers. Continuous fiber CMCs provide the best strengthening effect and produce stronger bonding between the fiber and matrix, improving toughness. They exhibit high mechanical strength even at high temperatures, high thermal shock resistance, stiffness, toughness, and thermal and corrosion resistance. CMCs are commonly fabricated using infiltration methods to introduce a ceramic matrix into a fiber preform.
Plaster mould casting is a metalworking process that uses plaster of paris moulds instead of sand. The plaster is mixed with additives to improve its strength and permeability. The process involves spraying a pattern with parting compound, pouring plaster around it, baking the mould to remove water, and then pouring molten metal into the mould cavity. It produces parts with good surface finish and accuracy, and can be used to cast small and complex non-ferrous metal parts.
Composite materials are engineered materials made from two or more constituent materials with different physical or chemical properties. The materials remain separate within the finished structure. One material, called the reinforcing phase, is embedded in the other material called the matrix phase. Common examples include concrete, where aggregates are embedded in cement, and fiberglass, where glass fibers are embedded in a polymer matrix. Composites are used because their overall properties are superior to their individual components. Some of the oldest composites include wattle and daub and concrete, and composites now make up common materials like asphalt, fiberglass, cement, and plywood.
This document provides an overview of metal matrix composites (MMC) and ceramic matrix composites (CMC). It defines composites as materials created by combining two or more materials, with fibers providing strength and stiffness. MMCs use a metal matrix such as aluminum reinforced with fibers like carbon fiber. The matrix holds the fibers and transfers load. CMCs use a ceramic matrix like silicon carbide reinforced with fibers like carbon fiber. Common applications of MMCs include automotive parts and bicycle frames due to their strength and light weight. CMCs are used in applications requiring heat resistance like rocket engine nozzles. Manufacturing methods for both include powder blending and liquid infiltration of the matrix around fibers.
Maraging steels are carbon-free iron alloys that are strengthened through precipitation hardening rather than carbon content. They contain additions of nickel, cobalt, molybdenum, titanium, and aluminum. Maraging steels are heat treated through solution treatment to form a martensitic structure, followed by aging to precipitate hardening intermetallic compounds within the martensite. This provides maraging steels with ultra-high strength even at elevated temperatures, along with excellent toughness. Common applications include aerospace components, ordnance, and tooling due to their combination of high strength, corrosion resistance, and fatigue endurance.
Seminar on tribological behaviour of alumina reinfoeced composite material na...Sidharth Adhikari
THIS SEMINAR IS ON TRIBOLOGY BEHAVIOR OF ALUMINA REINFOCED COMPOSITE MATERIAL AND BRAKE DISK MATERIAL
MTECH SECOND SEMESTER SEMINAR ,CENTRE FOR ADVANCE POST-GRADUATE STUDIES,BPUT,ROURKELA
This document discusses composite materials, including their history, components, types, applications, advantages, and disadvantages. Composite materials are composed of two or more constituent materials that differ in composition and remain separate when combined. Historically, Egyptians used mud and straw composites in 1500 BC, while Mongols invented composite bows in the 1200s using wood, bone, and glue. Modern composites use plastics and fibers and have stronger, stiffer, and lighter properties than metals. They contain a matrix, such as polymer, metal, or ceramic, that is reinforced with fibers or particles. Common composites include fiberglass, carbon fiber, and Kevlar in various matrices. Their advantages include tailorable properties while disadvantages include cost
Nitriding is a heat treatment process that diffuses nitrogen into the surface of metals like steel to create a hardened case. There are three main nitriding methods: gas, salt bath, and plasma nitriding. Nitriding increases properties like wear resistance, fatigue strength, and corrosion resistance while minimizing distortion compared to other hardening processes. Common applications of nitrided parts include use in the aircraft, automotive, and tooling industries.
This document provides an overview of functionally graded materials (FGMs). It discusses that FGMs are materials that have a gradual, continuous change in composition and properties across their volume, as seen in nature. The document outlines the history of FGMs, introduces their characteristics including continuous property variation, and describes various processing methods used to manufacture them like powder metallurgy and deposition techniques. Finally, the document discusses applications of FGMs in fields like aerospace, electronics, and biomedicine and notes challenges in developing FGM models and reducing costs.
The document provides an overview of metal matrix composites (MMCs). It discusses that MMCs consist of a metal matrix reinforced with ceramic particles or fibers. The reinforcement improves the composite's properties over the unreinforced metal, such as increased strength and stiffness. The document also examines the important interfaces between the matrix and reinforcement, which influence the composite's performance. It describes various bonding mechanisms at the interface like mechanical, chemical, and diffusion bonding. Finally, the document outlines common processing techniques for fabricating MMCs, including powder metallurgy where metal powders are compacted and sintered to form the final composite material.
The document discusses the classification of composite materials based on the geometry of reinforcement. It defines composites as materials made from two or more constituent materials that produce different properties than the individual components. Composites are classified based on the matrix material, such as polymer, metal, ceramic, or carbon/carbon, and also based on the geometry of reinforcement, including particulate, whisker/flake, or fiber reinforcement. Fiber reinforced composites use fibers as the reinforcement to enhance the strength and properties of the matrix material. Different types of reinforced composites are then discussed, such as filled, whiskers, flakes, and particulate reinforced composites.
The document discusses fundamentals of stainless steel production using the electric arc furnace - argon oxygen decarburization (EAF-AOD) route. Key points include:
1) Preferential oxidation of carbon over chromium is desired to avoid chromium losses to slag. High temperature and reduced carbon monoxide partial pressure favor carbon oxidation.
2) Slag composition and properties are important for efficient chromium recovery, with optimal basicity between 1.3-1.8 and 6-8% aluminum oxide needed.
3) Nitrogen control involves adsorption/desorption kinetics and can be managed through blowing procedures and argon rinsing in the AOD process.
Shot blasting is a process used in many industries to clean, strengthen, and polish surfaces by blasting a mixture of abrasive materials against them under high pressure. Specifically, steel shot blasting involves using a turbine to accelerate and project a steady stream of small stainless steel balls or "shot" against a surface, with smaller shot producing a smoother finish and larger shot a rougher finish.
This document provides an overview of composite materials, including their advantages and disadvantages, applications, and different types. It discusses polymer matrix composites, metal matrix composites, and ceramic matrix composites. Metal matrix composites provide advantages over monolithic metals like higher strength and lower thermal expansion. Applications include use in space shuttles, military equipment, and transportation. Ceramic matrix composites are used in high temperature applications. Carbon-carbon composites can withstand very high temperatures up to 3315°C and are lighter than other materials.
The document discusses ceramic matrix composites (CMCs), including the materials and processing methods used to produce them. It describes common matrix materials like Al2O3 and SiC and reinforcements like fibers and whiskers. Popular fabrication techniques are outlined, such as chemical vapor infiltration, polymer infiltration and pyrolysis, melt infiltration, and slurry infiltration. The mechanical properties of CMCs are summarized, focusing on fracture toughness which is improved through mechanisms like crack deflection and fiber pull-out. Specific CMC systems analyzed include SiC-SiC, ZrB2-SiC, TiB2-SiC, and Al2O3-SiC composites.
The document is a catalog from Beijing Sino Steel Engineering & Equipment Co., Ltd. that describes various refractory products including nozzles, well blocks, impact plates, and stoppers. It provides details on the applications and physical/chemical properties of each type of product. The products are designed for use in steelmaking facilities and equipment such as ladles, tundishes, and continuous casting machines.
Composite materials are a combination of two or more materials that result in properties superior to the individual components. They consist of a reinforcement phase, such as fibers, embedded within a binder or matrix phase. Composites offer advantages like high strength and stiffness with low weight. Common applications include aerospace, automotive, sports equipment and construction. The two main categories of composites are polymer matrix composites and metal matrix composites. Fiber reinforced polymers are the most widely used type and consist of fibers, such as glass, carbon or aramid, embedded in a polymer matrix.
This document presents an overview of metal matrix composites (MMCs). It defines MMCs as composites with at least two constituent parts, one being a metal matrix and the other being another material like another metal, ceramic, or organic compound. The document discusses the composition, production, properties and applications of MMCs. It notes that MMCs combine properties like high strength and stiffness with lower density compared to unreinforced metals. Common reinforcement materials in MMCs include fibers of boron, silicon carbide, and alumina. The document outlines some important MMC systems and their advantages like higher temperature capability and strengths, as well as disadvantages like higher cost. Applications discussed include automotive and aerospace parts.
This document provides an overview of composite materials. It defines composites as materials made of two or more constituent materials with distinct properties. Composites consist of a reinforcement material embedded in a matrix to hold the reinforcements together. Common reinforcements include fibers, particles or flakes. The matrix materials are typically polymers, metals or ceramics. The document discusses various types of composites and their applications in areas like transportation, aerospace, sports equipment and infrastructure. Composites offer advantages like high strength, stiffness and corrosion resistance combined with lighter weight.
Ceramic matrix composites (CMCs) consist of ceramic fibers embedded in a ceramic matrix to form a ceramic fiber reinforced ceramic material. They improve the strength and toughness of brittle ceramics. CMCs can be reinforced with either short or continuous fibers. Continuous fiber CMCs provide the best strengthening effect and produce stronger bonding between the fiber and matrix, improving toughness. They exhibit high mechanical strength even at high temperatures, high thermal shock resistance, stiffness, toughness, and thermal and corrosion resistance. CMCs are commonly fabricated using infiltration methods to introduce a ceramic matrix into a fiber preform.
Plaster mould casting is a metalworking process that uses plaster of paris moulds instead of sand. The plaster is mixed with additives to improve its strength and permeability. The process involves spraying a pattern with parting compound, pouring plaster around it, baking the mould to remove water, and then pouring molten metal into the mould cavity. It produces parts with good surface finish and accuracy, and can be used to cast small and complex non-ferrous metal parts.
Composite materials are engineered materials made from two or more constituent materials with different physical or chemical properties. The materials remain separate within the finished structure. One material, called the reinforcing phase, is embedded in the other material called the matrix phase. Common examples include concrete, where aggregates are embedded in cement, and fiberglass, where glass fibers are embedded in a polymer matrix. Composites are used because their overall properties are superior to their individual components. Some of the oldest composites include wattle and daub and concrete, and composites now make up common materials like asphalt, fiberglass, cement, and plywood.
This document provides an overview of metal matrix composites (MMC) and ceramic matrix composites (CMC). It defines composites as materials created by combining two or more materials, with fibers providing strength and stiffness. MMCs use a metal matrix such as aluminum reinforced with fibers like carbon fiber. The matrix holds the fibers and transfers load. CMCs use a ceramic matrix like silicon carbide reinforced with fibers like carbon fiber. Common applications of MMCs include automotive parts and bicycle frames due to their strength and light weight. CMCs are used in applications requiring heat resistance like rocket engine nozzles. Manufacturing methods for both include powder blending and liquid infiltration of the matrix around fibers.
Maraging steels are carbon-free iron alloys that are strengthened through precipitation hardening rather than carbon content. They contain additions of nickel, cobalt, molybdenum, titanium, and aluminum. Maraging steels are heat treated through solution treatment to form a martensitic structure, followed by aging to precipitate hardening intermetallic compounds within the martensite. This provides maraging steels with ultra-high strength even at elevated temperatures, along with excellent toughness. Common applications include aerospace components, ordnance, and tooling due to their combination of high strength, corrosion resistance, and fatigue endurance.
Seminar on tribological behaviour of alumina reinfoeced composite material na...Sidharth Adhikari
THIS SEMINAR IS ON TRIBOLOGY BEHAVIOR OF ALUMINA REINFOCED COMPOSITE MATERIAL AND BRAKE DISK MATERIAL
MTECH SECOND SEMESTER SEMINAR ,CENTRE FOR ADVANCE POST-GRADUATE STUDIES,BPUT,ROURKELA
This document discusses composite materials, including their history, components, types, applications, advantages, and disadvantages. Composite materials are composed of two or more constituent materials that differ in composition and remain separate when combined. Historically, Egyptians used mud and straw composites in 1500 BC, while Mongols invented composite bows in the 1200s using wood, bone, and glue. Modern composites use plastics and fibers and have stronger, stiffer, and lighter properties than metals. They contain a matrix, such as polymer, metal, or ceramic, that is reinforced with fibers or particles. Common composites include fiberglass, carbon fiber, and Kevlar in various matrices. Their advantages include tailorable properties while disadvantages include cost
Nitriding is a heat treatment process that diffuses nitrogen into the surface of metals like steel to create a hardened case. There are three main nitriding methods: gas, salt bath, and plasma nitriding. Nitriding increases properties like wear resistance, fatigue strength, and corrosion resistance while minimizing distortion compared to other hardening processes. Common applications of nitrided parts include use in the aircraft, automotive, and tooling industries.
This document provides an overview of functionally graded materials (FGMs). It discusses that FGMs are materials that have a gradual, continuous change in composition and properties across their volume, as seen in nature. The document outlines the history of FGMs, introduces their characteristics including continuous property variation, and describes various processing methods used to manufacture them like powder metallurgy and deposition techniques. Finally, the document discusses applications of FGMs in fields like aerospace, electronics, and biomedicine and notes challenges in developing FGM models and reducing costs.
The document provides an overview of metal matrix composites (MMCs). It discusses that MMCs consist of a metal matrix reinforced with ceramic particles or fibers. The reinforcement improves the composite's properties over the unreinforced metal, such as increased strength and stiffness. The document also examines the important interfaces between the matrix and reinforcement, which influence the composite's performance. It describes various bonding mechanisms at the interface like mechanical, chemical, and diffusion bonding. Finally, the document outlines common processing techniques for fabricating MMCs, including powder metallurgy where metal powders are compacted and sintered to form the final composite material.
The document discusses the classification of composite materials based on the geometry of reinforcement. It defines composites as materials made from two or more constituent materials that produce different properties than the individual components. Composites are classified based on the matrix material, such as polymer, metal, ceramic, or carbon/carbon, and also based on the geometry of reinforcement, including particulate, whisker/flake, or fiber reinforcement. Fiber reinforced composites use fibers as the reinforcement to enhance the strength and properties of the matrix material. Different types of reinforced composites are then discussed, such as filled, whiskers, flakes, and particulate reinforced composites.
The document discusses fundamentals of stainless steel production using the electric arc furnace - argon oxygen decarburization (EAF-AOD) route. Key points include:
1) Preferential oxidation of carbon over chromium is desired to avoid chromium losses to slag. High temperature and reduced carbon monoxide partial pressure favor carbon oxidation.
2) Slag composition and properties are important for efficient chromium recovery, with optimal basicity between 1.3-1.8 and 6-8% aluminum oxide needed.
3) Nitrogen control involves adsorption/desorption kinetics and can be managed through blowing procedures and argon rinsing in the AOD process.
Shot blasting is a process used in many industries to clean, strengthen, and polish surfaces by blasting a mixture of abrasive materials against them under high pressure. Specifically, steel shot blasting involves using a turbine to accelerate and project a steady stream of small stainless steel balls or "shot" against a surface, with smaller shot producing a smoother finish and larger shot a rougher finish.
This document provides an overview of composite materials, including their advantages and disadvantages, applications, and different types. It discusses polymer matrix composites, metal matrix composites, and ceramic matrix composites. Metal matrix composites provide advantages over monolithic metals like higher strength and lower thermal expansion. Applications include use in space shuttles, military equipment, and transportation. Ceramic matrix composites are used in high temperature applications. Carbon-carbon composites can withstand very high temperatures up to 3315°C and are lighter than other materials.
The document discusses ceramic matrix composites (CMCs), including the materials and processing methods used to produce them. It describes common matrix materials like Al2O3 and SiC and reinforcements like fibers and whiskers. Popular fabrication techniques are outlined, such as chemical vapor infiltration, polymer infiltration and pyrolysis, melt infiltration, and slurry infiltration. The mechanical properties of CMCs are summarized, focusing on fracture toughness which is improved through mechanisms like crack deflection and fiber pull-out. Specific CMC systems analyzed include SiC-SiC, ZrB2-SiC, TiB2-SiC, and Al2O3-SiC composites.
The document is a catalog from Beijing Sino Steel Engineering & Equipment Co., Ltd. that describes various refractory products including nozzles, well blocks, impact plates, and stoppers. It provides details on the applications and physical/chemical properties of each type of product. The products are designed for use in steelmaking facilities and equipment such as ladles, tundishes, and continuous casting machines.
Composite materials are a combination of two or more materials that result in properties superior to the individual components. They consist of a reinforcement phase, such as fibers, embedded within a binder or matrix phase. Composites offer advantages like high strength and stiffness with low weight. Common applications include aerospace, automotive, sports equipment and construction. The two main categories of composites are polymer matrix composites and metal matrix composites. Fiber reinforced polymers are the most widely used type and consist of fibers, such as glass, carbon or aramid, embedded in a polymer matrix.
This document provides an overview of composite materials, including definitions, key components, types of composites, and applications. It defines a composite as a material made from two or more constituent materials combined to give unique properties. Composites consist of a reinforcement material, such as fibers, and a matrix that holds the reinforcements together. The document describes different types of reinforcements, matrices, and the roles they play in composites. It also outlines various composite material types and their applications in industries such as aerospace, automotive, marine, and consumer goods.
This document provides an overview of composite materials. It defines a composite as a material made of two or more physically distinct phases that produce properties different from the individual components. The document discusses various types of composite materials, including metal matrix composites, ceramic matrix composites, and polymer matrix composites. It also covers the classification of composites, functions of the matrix, reinforcing phases, properties, processing techniques, and applications.
Composits material. Engineering material and scinece.pptxhamzakhan396556
The document describes composite materials as consisting of two or more physically distinct phases that produce properties different from the individual phases. A composite generally has one material forming a continuous matrix and another providing reinforcement. Examples given are concrete reinforced with steel and epoxy reinforced with graphite fibers. Composites are classified based on their matrix material, which can be polymer, metal, or ceramic. The reinforcement can be fibers, particles, or flakes. Fiber-reinforced polymer composites are the most widely used type of composite.
Here are the steps to solve this problem:
(i) Using the rule of mixtures:
Ec = VfEf + VmEm
= 0.4(69 GPa) + 0.6(3.4 GPa) = 30 GPa
(ii) Load carried by fibers = VfσcAc = 0.4(50 MPa)(250 mm2) = 5,000 N
Load carried by matrix = VmσcAc = 0.6(50 MPa)(250 mm2) = 6,000 N
(iii) Strain in fibers = εf = σc/Ef = 50 MPa/69 GPa = 1.69 x 10
Dr P R Rathod from L D College of Engineering in Ahmedabad provides a document discussing composite materials. The document defines composites as materials composed of two or more chemically distinct phases at the microscopic scale that have significantly different properties. It then discusses the history of composites dating back to ancient uses of materials like papyrus and straw bricks. It also provides examples of composites in everyday life like concrete, wood, and the human body. The document then covers various topics related to composites including their constituents, classification based on matrix and reinforcement, fiber reinforced composites, and structural composite materials like laminates and sandwich structures.
Composites consist of a combination of two or more materials, with a matrix and fiber reinforcement. The matrix holds the fibers together and typically transfers stress between fibers. Common matrix materials include polymers and metals. Fibers provide strength and stiffness and can be made of materials like glass, carbon, and Kevlar. Composites offer advantages over traditional materials like high strength to weight ratio, corrosion resistance, and anisotropic properties that allow for tailored designs. However, they also have disadvantages like higher costs and more complex manufacturing compared to metals.
Composite materials are composed of two or more distinct materials that have improved properties over the individual materials. The document discusses various types of composite materials including particle-reinforced, fiber-reinforced, and structural composites. It describes the matrix and dispersed phases, and how their interaction leads to improved properties. Different classifications of composites are also covered based on the matrix material and reinforcement structure. A wide range of applications are mentioned stemming from the composites' high strength, stiffness, and low density properties.
This document provides an introduction to composite materials. It defines composites as materials made of two or more inherently different materials that when combined produce properties exceeding the individual components. The matrix holds the reinforcement and transfers load, while the reinforcement provides properties like strength and stiffness. Common matrix materials include epoxies, metals, and ceramics. Fiber reinforcements include glass, carbon, and aramid fibers. The document discusses different types of composites and their applications, advantages like high strength and design flexibility, and disadvantages like anisotropic properties and difficulties in inspection.
Composite materials are composed of two or more physically distinct phases that produce properties different from the individual components. Composites can be very strong yet light weight. Examples include fiberglass, carbon fiber reinforced plastics, and cemented carbides. Composites find applications in aerospace, automotive, sports equipment due to their high strength to weight ratio and other advantageous properties. They are classified based on matrix material (polymer, metal, ceramic) and type of reinforcement (particles, fibers).
Composite materials are combinations of two or more materials that result in unique properties. They have advantages like high strength to weight ratio, energy efficiency, and corrosion resistance. Composites can be classified by their matrix, which can be a metal, ceramic, or polymer. Fiber reinforced polymer composites are commonly manufactured using techniques like hand layup, filament winding, resin transfer molding, and pultrusion. Proper fiber length, orientation and bonding with the matrix are important for composite strength and properties.
Composite materials consist of a matrix and reinforcement. The matrix holds the reinforcement in place and transfers loads to the reinforcement. Common reinforcements include fibers, particles or flakes. Composites provide benefits like improved strength to weight ratio, corrosion resistance and design flexibility compared to traditional materials. They are used widely in applications like aircraft, automotive, sports equipment, buildings and more due to their desirable properties and performance advantages.
This document discusses composite materials and provides classifications. It begins by defining composite materials as materials made from two or more constituent materials with different physical or chemical properties. Composites are then classified into two levels: by matrix (organic, metal, ceramic) and by reinforcement form (fiber reinforced, laminar, particulate). Fiber reinforced composites can be continuous or discontinuous. Conventional materials like plastics, ceramics, and metals are also discussed and their advantages and limitations compared. The document provides an overview of composite materials and classifications.
This document discusses different types of advanced engineering materials including metals, ceramics, polymers, organics, composites, and emerging nanomaterials. Metals are dense, high melting point materials that are ductile while ceramics are brittle with very high melting points and elastic modulus. Polymers have low density and melting points with variable strength and stiffness properties. Composites like fiber reinforced plastics combine fibers with polymer, metal, or ceramic matrices to produce materials with optimized properties. Emerging nanomaterials such as fullerenes, carbon nanotubes, and aerogels utilize the unique properties of materials at the nano-scale.
Composite materials are composed of two or more physically distinct materials that produce improved properties over the individual components. The document discusses various types of composite materials including fiber-reinforced polymers, metal matrix composites, ceramic matrix composites, and hybrid composites. It also describes the key characteristics of the matrix and reinforcing phases including their functions, essential properties, and various forms like fibers, particles, flakes that the reinforcing phase can take. Common applications of structural composites in aircraft and construction are also mentioned.
The document discusses various types of fibers and matrices used in fiber-reinforced composites. It describes the main functions of fibers as carrying loads and matrices as binding fibers together and protecting them. Common fiber types include glass, carbon, aramid, boron, quartz, and metal fibers. Resin matrices like epoxy, polyester and phenolic are frequently used. Fillers can be added to composites to reduce costs, improve workability or impart special properties. Glass fibers are the most widely used due to their low cost and high strength and stiffness relative to cost. Carbon and aramid fibers have very high strength but are more expensive.
Material science and engineering is an interdisciplinary field that develops new materials and improves existing ones by understanding microstructure-composition-processing relationships. The field studies how a material's structure, synthesis, and processing affect its properties. Material scientists focus on underlying relationships between synthesis, processing, structure and properties, while material engineers translate materials into useful devices by controlling synthesis and processing to achieve desired structures and properties.
Generative AI Use cases applications solutions and implementation.pdfmahaffeycheryld
Generative AI solutions encompass a range of capabilities from content creation to complex problem-solving across industries. Implementing generative AI involves identifying specific business needs, developing tailored AI models using techniques like GANs and VAEs, and integrating these models into existing workflows. Data quality and continuous model refinement are crucial for effective implementation. Businesses must also consider ethical implications and ensure transparency in AI decision-making. Generative AI's implementation aims to enhance efficiency, creativity, and innovation by leveraging autonomous generation and sophisticated learning algorithms to meet diverse business challenges.
https://www.leewayhertz.com/generative-ai-use-cases-and-applications/
Supermarket Management System Project Report.pdfKamal Acharya
Supermarket management is a stand-alone J2EE using Eclipse Juno program.
This project contains all the necessary required information about maintaining
the supermarket billing system.
The core idea of this project to minimize the paper work and centralize the
data. Here all the communication is taken in secure manner. That is, in this
application the information will be stored in client itself. For further security the
data base is stored in the back-end oracle and so no intruders can access it.
Levelised Cost of Hydrogen (LCOH) Calculator ManualMassimo Talia
The aim of this manual is to explain the
methodology behind the Levelized Cost of
Hydrogen (LCOH) calculator. Moreover, this
manual also demonstrates how the calculator
can be used for estimating the expenses associated with hydrogen production in Europe
using low-temperature electrolysis considering different sources of electricity
Digital Twins Computer Networking Paper Presentation.pptxaryanpankaj78
A Digital Twin in computer networking is a virtual representation of a physical network, used to simulate, analyze, and optimize network performance and reliability. It leverages real-time data to enhance network management, predict issues, and improve decision-making processes.
Road construction is not as easy as it seems to be, it includes various steps and it starts with its designing and
structure including the traffic volume consideration. Then base layer is done by bulldozers and levelers and after
base surface coating has to be done. For giving road a smooth surface with flexibility, Asphalt concrete is used.
Asphalt requires an aggregate sub base material layer, and then a base layer to be put into first place. Asphalt road
construction is formulated to support the heavy traffic load and climatic conditions. It is 100% recyclable and
saving non renewable natural resources.
With the advancement of technology, Asphalt technology gives assurance about the good drainage system and with
skid resistance it can be used where safety is necessary such as outsidethe schools.
The largest use of Asphalt is for making asphalt concrete for road surfaces. It is widely used in airports around the
world due to the sturdiness and ability to be repaired quickly, it is widely used for runways dedicated to aircraft
landing and taking off. Asphalt is normally stored and transported at 150’C or 300’F temperature
DEEP LEARNING FOR SMART GRID INTRUSION DETECTION: A HYBRID CNN-LSTM-BASED MODELijaia
As digital technology becomes more deeply embedded in power systems, protecting the communication
networks of Smart Grids (SG) has emerged as a critical concern. Distributed Network Protocol 3 (DNP3)
represents a multi-tiered application layer protocol extensively utilized in Supervisory Control and Data
Acquisition (SCADA)-based smart grids to facilitate real-time data gathering and control functionalities.
Robust Intrusion Detection Systems (IDS) are necessary for early threat detection and mitigation because
of the interconnection of these networks, which makes them vulnerable to a variety of cyberattacks. To
solve this issue, this paper develops a hybrid Deep Learning (DL) model specifically designed for intrusion
detection in smart grids. The proposed approach is a combination of the Convolutional Neural Network
(CNN) and the Long-Short-Term Memory algorithms (LSTM). We employed a recent intrusion detection
dataset (DNP3), which focuses on unauthorized commands and Denial of Service (DoS) cyberattacks, to
train and test our model. The results of our experiments show that our CNN-LSTM method is much better
at finding smart grid intrusions than other deep learning algorithms used for classification. In addition,
our proposed approach improves accuracy, precision, recall, and F1 score, achieving a high detection
accuracy rate of 99.50%.
Tools & Techniques for Commissioning and Maintaining PV Systems W-Animations ...Transcat
Join us for this solutions-based webinar on the tools and techniques for commissioning and maintaining PV Systems. In this session, we'll review the process of building and maintaining a solar array, starting with installation and commissioning, then reviewing operations and maintenance of the system. This course will review insulation resistance testing, I-V curve testing, earth-bond continuity, ground resistance testing, performance tests, visual inspections, ground and arc fault testing procedures, and power quality analysis.
Fluke Solar Application Specialist Will White is presenting on this engaging topic:
Will has worked in the renewable energy industry since 2005, first as an installer for a small east coast solar integrator before adding sales, design, and project management to his skillset. In 2022, Will joined Fluke as a solar application specialist, where he supports their renewable energy testing equipment like IV-curve tracers, electrical meters, and thermal imaging cameras. Experienced in wind power, solar thermal, energy storage, and all scales of PV, Will has primarily focused on residential and small commercial systems. He is passionate about implementing high-quality, code-compliant installation techniques.
1. ME 429
Introduction to Composite Materials
Dr. Ahmet Erkliğ
2005-2006 Fall Semester
www1.gantep.edu.tr/~erklig/me4
29/introduction.ppt, 13 Dec
2010
2. Composite materials – Introduction
Definition: any combination of two or more different
materials at the macroscopic level.
OR
Two inherently different materials that when
combined together produce a material with
properties that exceed the constituent materials.
Reinforcement phase (e.g., Fibers)
Binder phase (e.g., compliant matrix)
Advantages
High strength and stiffness
Low weight ratio
Material can be designed in addition to the structure
3. Applications
Straw in clay construction by Egyptians
Aerospace industry
Sporting goods
Automotive
Construction
4. Types of Composites
Matrix
phase/Reinforc
ement Phase
Metal Ceramic Polymer
Metal Powder metallurgy
parts – combining
immiscible metals
Cermets (ceramic-
metal composite)
Brake pads
Ceramic Cermets, TiC, TiCN
Cemented carbides –
used in tools
Fiber-reinforced
metals
SiC reinforced
Al2O3
Tool materials
Fiberglass
Polymer Kevlar fibers in an
epoxy matrix
Elemental
(Carbon,
Boron, etc.)
Fiber reinforced
metals
Auto parts
aerospace
Rubber with
carbon (tires)
Boron, Carbon
reinforced plastics
MMC’s CMC’s PMC’s
Metal Matrix Composites Ceramic Matrix Comp’s. Polymer Matrix Comp’s
5. Costs of composite manufacture
Material costs -- higher for composites
Constituent materials (e.g., fibers and resin)
Processing costs -- embedding fibers in matrix
not required for metals Carbon fibers order of magnitude
higher than aluminum
Design costs -- lower for composites
Can reduce the number of parts in a complex
assembly by designing the material in combination
with the structure
Increased performance must justify higher
material costs
6. Types of Composite Materials
There are five basic types of composite materials:
Fiber, particle, flake, laminar or layered and filled
composites.
7. A. Fiber Composites
In fiber composites, the fibers reinforce along the line of
their length. Reinforcement may be mainly 1-D, 2-D or 3-D.
Figure shows the three basic types of fiber orientation.
1-D gives maximum strength in
one direction.
2-D gives strength in two
directions.
Isotropic gives strength equally
in all directions.
8. Composite strength depends on following factors:
Inherent fiber strength,
Fiber length, Number of
flaws
Fiber shape
The bonding of the
fiber (equally stress
distribution)
Voids
Moisture (coupling
agents)
9. B. Particle Composites
Particles usually reinforce a composite equally in all directions
(called isotropic). Plastics, cermets and metals are examples of
particles.
Particles used to strengthen a matrix do not do so in the same
way as fibers. For one thing, particles are not directional like
fibers. Spread at random through out a matrix, particles tend to
reinforce in all directions equally.
Cermets
(1) Oxide–Based cermets
(e.g. Combination of Al2O3 with Cr)
(2) Carbide–Based Cermets
(e.g. Tungsten–carbide, titanium–carbide)
Metal–plastic particle composites
(e.g. Aluminum, iron & steel, copper particles)
Metal–in–metal Particle Composites and
Dispersion Hardened Alloys
(e.g. Ceramic–oxide particles)
10. C. Flake Composites - 1
Flakes, because of their shape, usually
reinforce in 2-D. Two common flake
materials are glass and mica. (Also
aluminum is used as metal flakes)
11. C. Flake Composites -2
A flake composite consists of thin, flat flakes
held together by a binder or placed in a
matrix. Almost all flake composite matrixes
are plastic resins. The most important flake
materials are:
1. Aluminum
2. Mica
3. Glass
12. C. Flake Composites -3
Basically, flakes will provide:
Uniform mechanical properties in the plane of
the flakes
Higher strength
Higher flexural modulus
Higher dielectric strength and heat resistance
Better resistance to penetration by liquids and
vapor
Lower cost
13. D. Laminar Composites - 1
Laminar composites involve two or more
layers of the same or different materials. The
layers can be arranged in different directions
to give strength where needed. Speedboat
hulls are among the very many products of
this kind.
14. D. Laminar Composites - 2
Like all composites laminar composites
aim at combining constituents to produce
properties that neither constituent alone
would have.
In laminar composites outer metal is not
called a matrix but a face. The inner
metal, even if stronger, is not called a
reinforcement. It is called a base.
15. D. Laminar Composites - 3
We can divide laminar composites into three basic types:
Unreinforced–layer composites
(1) All–Metal
(a) Plated and coated metals (electrogalvanized
steel – steel plated with zinc)
(b) Clad metals (aluminum–clad, copper–clad)
(c) Multilayer metal laminates (tungsten, beryllium)
(2) Metal–Nonmetal (metal with plastic, rubber, etc.)
(3) Nonmetal (glass–plastic laminates, etc.)
Reinforced–layer composites (laminae and laminates)
Combined composites (reinforced–plastic laminates
well bonded with steel, aluminum, copper, rubber,
gold, etc.)
16. D. Laminar Composites - 4
A lamina (laminae) is any
arrangement of unidirectional
or woven fibers in a matrix.
Usually this arrangement is
flat, although it may be
curved, as in a shell.
A laminate is a stack of
lamina arranged with their
main reinforcement in at least
two different directions.
17. E. Filled Composites
There are two types of filled composites. In
one, filler materials are added to a normal
composite result in strengthening the
composite and reducing weight. The second
type of filled composite consists of a skeletal
3-D matrix holding a second material. The
most widely used composites of this kind are
sandwich structures and honeycombs.
18. F. Combined Composites
It is possible to combine
several different materials
into a single composite. It is
also possible to combine
several different composites
into a single product. A good
example is a modern ski.
(combination of wood as
natural fiber, and layers as
laminar composites)
19. Forms of Reinforcement Phase
Fibers
cross-section can be circular, square or hexagonal
Diameters --> 0.0001” - 0.005 “
Lengths --> L/D ratio
100 -- for chopped fiber
much longer for continuous fiber
Particulate
small particles that impede dislocation movement
(in metal composites) and strengthens the matrix
For sizes > 1 mm, strength of particle is involves in
load sharing with matrix
Flakes
flat platelet form
20. Fiber Reinforcement
The typical composite consists of a matrix holding
reinforcing materials. The reinforcing materials, the
most important is the fibers, supply the basic
strength of the composite. However, reinforcing
materials can contribute much more than strength.
They can conduct heat or resist chemical corrosion.
They can resist or conduct electricity. They may be
chosen for their stiffness (modulus of elasticity) or for
many other properties.
21. Types of Fibers
The fibers are divided into two main groups:
Glass fibers: There are many different kinds of glass,
ranging from ordinary bottle glass to high purity quartz
glass. All of these glasses can be made into fibers.
Each offers its own set of properties.
Advanced fibers: These materials offer high strength
and high stiffness at low weight. Boron, silicon, carbide
and graphite fibers are in this category. So are the
aramids, a group of plastic fibers of the polyamide
(nylon) family.
22. Fibers - Glass
Fiberglass properties vary somewhat according to the type of glass
used. However, glass in general has several well–known
properties that contribute to its great usefulness as a reinforcing
agent:
Tensile strength
Chemical resistance
Moisture resistance
Thermal properties
Electrical properties
There are four main types of glass used in fiberglass:
A–glass
C–glass
E–glass
S–glass
23. Fibers - Glass
Most widely used fiber
Uses: piping, tanks, boats, sporting goods
Advantages
Low cost
Corrosion resistance
Low cost relative to other composites:
Disadvantages
Relatively low strength
High elongation
Moderate strength and weight
Types:
E-Glass - electrical, cheaper
S-Glass - high strength
24. Fibers - Aramid (kevlar, Twaron)
Uses:
high performance replacement for glass
fiber
Examples
Armor, protective clothing, industrial,
sporting goods
Advantages:
higher strength and lighter than glass
More ductile than carbon
25. Fibers - Carbon
2nd most widely used fiber
Examples
aerospace, sporting goods
Advantages
high stiffness and strength
Low density
Intermediate cost
Properties:
Standard modulus: 207-240 Gpa
Intermediate modulus: 240-340 GPa
High modulus: 340-960 GPa
Diameter: 5-8 microns, smaller than human hair
Fibers grouped into tows or yarns of 2-12k fibers
26. Fibers -- Carbon (2)
Types of carbon fiber
vary in strength with processing
Trade-off between strength and modulus
Intermediate modulus
PAN (Polyacrylonitrile)
fiber precursor heated and stretched to align structure
and remove non-carbon material
High modulus
made from petroleum pitch precursor at lower
cost
much lower strength
27. Fibers - Others
Boron
High stiffness, very high cost
Large diameter - 200 microns
Good compressive strength
Polyethylene - trade name: Spectra fiber
Textile industry
High strength
Extremely light weight
Low range of temperature usage
28. Fibers -- Others (2)
Ceramic Fibers (and matrices)
Very high temperature applications (e.g.
engine components)
Silicon carbide fiber - in whisker form.
Ceramic matrix so temperature resistance
is not compromised
Infrequent use
31. Matrix Materials
Functions of the matrix
Transmit force between fibers
arrest cracks from spreading between fibers
do not carry most of the load
hold fibers in proper orientation
protect fibers from environment
mechanical forces can cause cracks that allow
environment to affect fibers
Demands on matrix
Interlaminar shear strength
Toughness
Moisture/environmental resistance
Temperature properties
Cost
32. Matrices - Polymeric
Thermosets
cure by chemical reaction
Irreversible
Examples
Polyester, vinylester
Most common, lower cost, solvent resistance
Epoxy resins
Superior performance, relatively costly
33. Polyester
Polyesters have good mechanical properties, electrical
properties and chemical resistance. Polyesters are
amenable to multiple fabrication techniques and are low
cost.
Vinyl Esters
Vinyl Esters are similar to polyester in performance.
Vinyl esters have increased resistance to corrosive
environments as well as a high degree of moisture
resistance.
Matrices - Thermosets
34. Epoxy
Epoxies have improved strength and stiffness properties
over polyesters. Epoxies offer excellent corrosion
resistance and resistance to solvents and alkalis. Cure
cycles are usually longer than polyesters, however no
by-products are produced.
Flexibility and improved performance is also achieved
by the utilization of additives and fillers.
Matrices - Thermosets
35. Matrices - Thermoplastics
Formed by heating to elevated temperature
at which softening occurs
Reversible reaction
Can be reformed and/or repaired - not common
Limited in temperature range to 150C
Examples
Polypropylene
with nylon or glass
can be injected-- inexpensive
Soften layers of combined fiber and resin and
place in a mold -- higher costs
36. Matrices - Others
Metal Matrix Composites - higher
temperature
e.g., Aluminum with boron or carbon fibers
Ceramic matrix materials - very high
temperature
Fiber is used to add toughness, not
necessarily higher in strength and stiffness
37. Important Note
Composite properties are less than
that of the fiber because of dilution
by the matrix and the need to orient
fibers in different directions.
38. MANUFACTURING PROCESSES
OF COMPOSITES
Composite materials have succeeded remarkably in their
relatively short history. But for continued growth,
especially in structural uses, certain obstacles must be
overcome. A major one is the tendency of designers to
rely on traditional materials such as steel and aluminum
unless composites can be produced at lower cost.
Cost concerns have led to several changes in the
composites industry. There is a general movement
toward the use of less expensive fibers. For example,
graphite and aramid fibers have largely supplanted the
more costly boron in advanced–fiber composites. As
important as savings on materials may be, the real key
to cutting composite costs lies in the area of processing.
39. The processing of fiber reinforced laminates can be
divided into two main steps:
Lay–up
Curing
Curing is the drying and hardening (or polymerization) of
the resin matrix of a finished composite. This may be
done unaided or by applying heat and/or pressure.
Lay–up basically is the process of arranging fiber–
reinforced layers (laminae) in a laminate and shaping
the laminate to make the part desired. (The term lay–up
is also used to refer to the laminate itself before curing.)
Unless prepregs are used, lay–up includes the actual
creation of laminae by applying resins to fiber
reinforcements.
40. Laminate lay–up operations fall into three main
groups:
A. Winding and laying operations
B. Molding operations
C. Continuous lamination
Continuous lamination is relatively unimportant
compared with quality parameters as not good as wrt
other two processes. In this process, layers of fabric or
mat are passed through a resin dip and brought
together between cellophane covering sheets.
Laminate thickness and resin content are controlled by
squeegee rolls. The lay–up is passed through a heat
zone to cure the resin.
41. A. Winding Operation
The most important operation in this category is filament
winding. Fibers are passed through liquid resin, and then
wound onto a mandrel. After lay–up is completed, the
composite is cured on the mandrel. The mandrel is then
removed by melting, dissolving, breaking–out or some
other method.
42. B. Molding Operations
Molding operations are used in making a large number of
common composite products. There are two types of
processes:
A. Open–mold
(1) Hand lay–up
(2) Spray–up
(3) Vacuum–bag molding
(4) Pressure–bag molding
(5) Thermal expansion molding
(6) Autoclave molding
(7) Centrifugal casting
(8) Continuous pultrusion and pulforming.
43. 1. Hand Lay-up
Hand lay–up, or contact molding, is the oldest and
simplest way of making fiberglass–resin composites.
Applications are standard wind turbine blades, boats,
etc.)
44. 2. Spray-up
In Spray–up process, chopped fibers and resins are
sprayed simultaneously into or onto the mold. Applications
are lightly loaded structural panels, e.g. caravan bodies,
truck fairings, bathtubes, small boats, etc.
45. 3. Vacuum-Bag Molding
The vacuum–bag process was developed for making
a variety of components, including relatively large
parts with complex shapes. Applications are large
cruising boats, racecar components, etc.
46. 4. Pressure-Bag Molding
Pressure–bag process is virtually a mirror image of
vacuum–bag molding. Applications are sonar domes,
antenna housings, aircraft fairings, etc.
47. 5. Thermal Expansion Molding
In Thermal Expansion Molding process, prepreg layers
are wrapped around rubber blocks, and then placed in
a metal mold. As the entire assembly is heated, the
rubber expands more than the metal, putting pressure
on the laminate. Complex shapes can be made
reducing the need for later joining and fastening
operations.
48. 6. Autoclave Molding
Autoclave molding is similar to both vacuum–bag and
pressure–bag molding. Applications are lighter, faster
and more agile fighter aircraft, motor sport vehicles.
49. Continuous pultrusion
is the composite
counterpart of metal
extrusion. Complex
parts can be made.
7. Centrifugal Casting
Centrifugal Casting is used to form round objects such as
pipes.
8. Continuous Pultrusion and Pulforming
50. Pulforming is similar to pultrusion in many ways.
However, pultrusion is capable only of making straight
products that have the same volume all along their
lengths. Pulformed products, on the other hand, can be
either straight or curved, with changing shapes and
volumes. A typical pulformed product is a curved
reinforced plastic car spring. (shown in figure.)
51. B. Closed–mold
(1) Matched–die molding: As the name
suggests, a matched–die mold consists
of closely matched male and female
dies (shown in figure). Applications are
spacecraft parts, toys, etc.
(2) Injection molding: The injection
process begins with a thermosetting
(or sometimes thermoplastic) material
outside the mold. The plastic may
contain reinforcements or not. It is first
softened by heating and/or mechanical
working with an extrusion–type screw.
It is then forced, under high pressure
from a ram or screw, into the cool
mold. Applications are auto parts,
vanes, engine cowling defrosters and
aircraft radomes.
52. Material Forms and Manufacturing
Objectives of material production
assemble fibers
impregnate resin
shape product
cure resin
53. Sheet Molding Compound (SMC)
Chopped glass fiber added to polyester
resin mixture
•Question: Is SMC isotropic or anisotropic?
55. Prepregs
Prepreg and prepreg layup
“prepreg” - partially cured mixture of fiber
and resin
Unidirectional prepreg tape with paper backing
wound on spools
Cut and stacked
Curing conditions
Typical temperature and pressure in autoclave
is 120-200C, 100 psi
57. Material Forms
Textile forms
Braiding or weaving
Tubular braided form
can be flattened and cut for non-tubular
products
58. Fabric Structures
Woven: Series of Interlaced yarns at 90° to each other
Knit: Series of Interlooped Yarns
Braided: Series of Intertwined, Spiral Yarns
Nonwoven: Oriented fibers either mechanically,
chemically, or thermally bonded
59. Woven Fabrics
Basic woven fabrics consists of two
systems of yarns interlaced at right
angles to create a single layer with
isotropic or biaxial properties.
66. Braiding
A braid consists of two sets of yarns, which are helically
intertwined.
The resulting structure is oriented to the longitudinal axis
of the braid.
This structure is imparted with a high level of
conformability, relative low cost and ease of manufacture.
69. Triaxial Yarns
A system of longitudinal yarns can be introduced
which are held in place by the braiding yarns
These yarns will add dimensional stability, improve
tensile properties, stiffness and compressive strength.
Yarns can also be added to the core of the braid to
form a solid braid.
71. Resin transfer molding (RTM)
Dry-fiber preform placed in a closed
mold, resin injected into mold, then
cured
72. Material Forms
Pultrusion
Fiber and matrix are pulled through a
die, like extrusion of metals --
assembles fibers, impregnates the
resin, shapes the product, and cures
the resin in one step.
Example. Fishing rods